Public clouds are distributed computing systems where the cloud infrastructure is made available to the general public or a large industry group and the distributed computing system is typically owned by an organization selling cloud services. Public clouds allow users to share resources and applications in accordance with the scale of the use of each user. Because a public cloud typically serves many independent user entities, public cloud is a “multi-tenant environment.” Typically, in a public cloud, a single architecture hosts multiple customers' applications and data. A public cloud is one type of “public computer system.” Public computer systems directly solicits usage from at least a substantial portion of the general public (for example, directly solicits usage by anybody in a large industry group that includes many companies and individuals). Typically, a public computer system user must authenticate in some manner before a session that uses computing resources of the public computer system.
A “private cloud” is different than a public cloud. A private cloud is a term for a cloud infrastructure that is operated primarily to serve the computing needs of a single entity (for example, an individual, a company, a charitable organization). Resources utilized in a private cloud can be deployed internally. As such, rather than running web-based and rich client applications over the Internet, a private cloud can employ cloud computing within a company's own local or wide area networks. When the resources of a private cloud are located localized in this manner, the private cloud can be referred to as a “local cloud.” The term implies that the same virtualization and highly flexible and scalable methods used in huge Internet-based datacenters are also used in the private clouds in the enterprise. A cloud which is local and/or private is herein referred to as a “private/local cloud” or a “local/private cloud” (LPC). An LPC is one type of “local/private computer system.” Local/private computer systems (LPCSs) do not directly solicit usage by any substantial segment of the public. Typically, an LPCS user must authenticate a user in some manner before initiating a session that uses computing resources of the LPCS.
Sharing of resources of the public cloud becomes problematic when a customer monopolizes the resources, including but not limited to, bandwidth, disk I/O, CPU and other resources. The user who monopolizes is often referred to as a “noisy neighbor” and this user's behavior can negatively affect the performance of the cloud resources utilized by other users. A condition called “the noisy neighbor effect” occurs when an application or virtual machine uses the majority of available resources and causes network performance issues for others on the shared infrastructure. The noisy neighbor effect causes other virtual machines and applications that share the infrastructure to suffer from uneven cloud network performance. A lack of bandwidth is one cause of network performance issues and because bandwidth carries data throughout a network, when one application or instance uses too much, other applications suffer from slow speeds and/or latency.
To avoid the potential of this noisy neighbor effect, certain customers will utilize dedicated resources in a public cloud. In other words, a dedicated set of resources is “partitioned” to a respective public cloud customer, for example, by a resource management mechanism in the cloud. Alternatively, customers with potentially resource-intensive computing needs will use private computing environments, including proprietary distributed computing environments, such as private clouds. The users who are allocated dedicated resources in a public cloud can depend on consistent performance. But as a result of dedicating the partitioned sets of resources exclusively to these users, these dedicated resources are dormant when the corresponding the users are not computationally active.